Merge pull request #194 from gostool/leetcode0384

Leetcode0384
This commit is contained in:
halfrost
2021-11-25 23:57:29 -08:00
committed by GitHub
3 changed files with 159 additions and 0 deletions

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package leetcode
import "math/rand"
type Solution struct {
nums []int
}
func Constructor(nums []int) Solution {
return Solution{
nums: nums,
}
}
/** Resets the array to its original configuration and return it. */
func (this *Solution) Reset() []int {
return this.nums
}
/** Returns a random shuffling of the array. */
func (this *Solution) Shuffle() []int {
arr := make([]int, len(this.nums))
copy(arr, this.nums)
rand.Shuffle(len(arr), func(i, j int) {
arr[i], arr[j] = arr[j], arr[i]
})
return arr
}

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package leetcode
import (
"fmt"
"testing"
)
type question384 struct {
para384
ans384
}
// para 是参数
type para384 struct {
ops []string
value [][]int
}
// ans 是答案
type ans384 struct {
ans [][]int
}
func Test_Problem384(t *testing.T) {
qs := []question384{
{
para384{ops: []string{"Solution", "shuffle", "reset", "shuffle"}, value: [][]int{{1, 2, 3}, {}, {}, {}}},
ans384{[][]int{nil, {3, 1, 2}, {1, 2, 3}, {1, 3, 2}}},
},
}
fmt.Printf("------------------------Leetcode Problem 384------------------------\n")
for _, q := range qs {
sol := Constructor(nil)
_, p := q.ans384, q.para384
for _, op := range p.ops {
if op == "Solution" {
sol = Constructor(q.value[0])
} else if op == "reset" {
fmt.Printf("【input】:%v 【output】:%v\n", op, sol.Reset())
} else {
fmt.Printf("【input】:%v 【output】:%v\n", op, sol.Shuffle())
}
}
}
fmt.Printf("\n\n\n")
}

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# [384.Shuffle an Array](https://leetcode-cn.com/problems/shuffle-an-array/)
## 题目
Given an integer array nums, design an algorithm to randomly shuffle the array. All permutations of the array should be equally likely as a result of the shuffling.
Implement the Solution class:
- Solution(int[] nums) Initializes the object with the integer array nums.
- int[] reset() Resets the array to its original configuration and returns it.
- int[] shuffle() Returns a random shuffling of the array.
**Example 1**:
Input
["Solution", "shuffle", "reset", "shuffle"]
[[[1, 2, 3]], [], [], []]
Output
[null, [3, 1, 2], [1, 2, 3], [1, 3, 2]]
Explanation
Solution solution = new Solution([1, 2, 3]);
solution.shuffle(); // Shuffle the array [1,2,3] and return its result.
// Any permutation of [1,2,3] must be equally likely to be returned.
// Example: return [3, 1, 2]
solution.reset(); // Resets the array back to its original configuration [1,2,3]. Return [1, 2, 3]
solution.shuffle(); // Returns the random shuffling of array [1,2,3]. Example: return [1, 3, 2]
**Constraints:**
- 1 <= nums.length <= 200
- -1000000 <= nums[i] <= 1000000
- All the elements of nums are unique.
- At most 5 * 10000 calls in total will be made to reset and shuffle.
## 题目大意
给你一个整数数组 nums ,设计算法来打乱一个没有重复元素的数组。
实现 Solution class:
- Solution(int[] nums) 使用整数数组 nums 初始化对象
- int[] reset() 重设数组到它的初始状态并返回
- int[] shuffle() 返回数组随机打乱后的结果
## 解题思路
- 使用rand.Shuffle进行数组随机打乱
## 代码
```go
package leetcode
import "math/rand"
type Solution struct {
nums []int
}
func Constructor(nums []int) Solution {
return Solution{
nums: nums,
}
}
/** Resets the array to its original configuration and return it. */
func (this *Solution) Reset() []int {
return this.nums
}
/** Returns a random shuffling of the array. */
func (this *Solution) Shuffle() []int {
arr := make([]int, len(this.nums))
copy(arr, this.nums)
rand.Shuffle(len(arr), func(i, j int) {
arr[i], arr[j] = arr[j], arr[i]
})
return arr
}
```